C/2013 R1, also known as Comet ISON, is a long-period comet that was discovered on September 7, 2013. It is notable for its highly elliptical orbit, which brings it close to the Sun and then back out into the outer solar system. The comet was expected to become very bright as it approached the Sun, making it visible to the naked eye. The comet's closest approach to the Sun occurred on November 28, 2013. Unfortunately, it disintegrated during this perihelion passage, leading to a diminished visibility. Despite this, C/2013 R1 provided valuable data for astronomers studying the behavior and composition of comets.